People often find it desirable to participate in outdoor activities in hot weather. Such activities may include beachcombing, walking, jogging, sailing, biking, picnicking, attending an amusement park, watching sporting events, as well as a myriad of other pursuits. Nevertheless, when the ambient air is hot, these activities may be, at the least, uncomfortable, and, at worst, capable of causing adverse medical conditions such as dehydration and heat stroke.
Devices that act to deposit a mist of water on a user for the purpose of cooling the user rely on the fact that the evaporation of water is an endothermic process, meaning that it absorbs energy in the form heat. Accordingly, when small droplets of water are deposited on a user's skin and begin to evaporate, the user's skin is cooled. Converting the water to a fine spray by misting (i.e., atomization) helps to better coat the user's skin, adding to the effectiveness of this cooling effect.
There have been several attempts to produce portable misting devices for cooling. Information relevant to attempts can be found in, for example, U.S. Pat. No. 5,775,590 to Utter, U.S. Pat. No. 6,095,434 to Montenegro, and U.S. Pat. No. 6,189,805 to West et al (none of which are admitted as prior art by their inclusion herein). However, the devices described in the first two references require the user to manually pump the devices in order to produce a water mist. The user must, therefore, exert additional physical energy in the hot ambient in order to obtain any benefit from these devices. In contrast, the last reference utilizes a pump that pressurizes a tank of water above atmospheric pressure (e.g., 3 atmospheres) in order to force the water through downstream nozzles. Unfortunately, such a method for producing a water mist requires a robust, leak-proof tank in order to withstand the high pressures produced by the pump. Moreover, because of the danger of explosion, the condition of the tank and its pressurization must be carefully monitored.
For the foregoing reasons, there is a need for portable misting devices that address the above-described deficiencies.